Hi, thanks for asking! :)
How I feel about this character: Jin is awesome! Despite getting relatively little screen-time I feel like he is a very well characterized main-character. When I first started reading World Trigger after about 30 chapters had been translated, I found Jin interesting but was very annoyed at his sexual-harassment towards women which I still am.
In the beginning arcs he kind of appears…well, almighty, with his side-effect, the charisma he uses to get everybody on his side, his position and his Black Trigger. But a character that is too powerful is just boring. So I was very happy to learn more about Jin’s past and see moments in which he actually suffers and questions himself, becoming more “human”.
The fact that he has been so downcast during the current arc (due to Osamu’s injuries and Replica’s disappearance), really tugged at my heartstrings, though he seems to be recovering if the current match which he commentates is any indication.
All the people I ship romantically with this character: I ship Jin/taylorroseva(Tay) No that is not a joke, haha. Huh, you want me to ship him with an in-series character? Then Jin/Bonchi-Rice Crackers or Jin/staying alive and Jin/happiness. Seriously though, there is no actual human/humanoid within World Trigger that I really ship him with.
My non-romantic OTP for this character: Jin+ Tachikawa+Kazama, the rice-cracker-eating rival trio. Also Jin + Mikumo Squad. It’s SOOO ADORABLE when Jin PATS THEIR HEADS. I just really hope he won’t start groping Chika when she gets her growth spurt. How could I have forgot Jin+Tamakoma orz.
My unpopular opinion about this character:None, really.
One thing I wish would happen / had happened with this character in canon: I wish we would learn more about Jin in general. I’d like to know what is up with his father, if he even has one, and why he lives at the Tamakoma-Branch. According to chippokenabokura, we don’t even know what Jin is doing on a regular basis, while all the rest of the agents except Fuyushima and Amou(whose occupation we don’t know either) go attend school. And of course I don’t want him to get kidnapped or die but that’s already way more than one thing, haha. I’ve talked about it before, but I wish Ashihara had shown us the scene where Jin apologises to Chika and Osamu’s mom over and over again for Osamu’s heavy injuries, while seeming depressed. Most people, even in universe, think that Jin is very easy-going, but if this incident and all his work behind the scenes to prevent tragedy is any indication, he is incredibly earnest. Same with him helping Yuuma search for Replica.